It's always best to do a fresh install and save some of the end of your hard drive for backup (HDD Image Backup of the first partition & MBR using Acronis True Image 2011), this way you can quickly restore your computer should you have issues, rather than reinstalling everything. I use Linux (Ubuntu) to boot up my computer, then I use GParted to delete my hard drive, and partition in into 2 sections, first the primary partition, then I create an extended partition for backup... My Backups are for a completely configured system, so I usually leave at least 20 GB for the HDD Image (backup).

Furthermore, if you have to reinstall your OS Later, you will have to install the original OS, then redo the upgrade, so avoid upgrades AT ALL COST!

It's much easier to do a system restore from a system image using Acronis than any other method, furthermore it only takes around 5-30 minutes (Depending upon size) to do a restore using Acronis, and that my friend is precious, so make sure your computer is completely set up before you make the backup image! (My 64GB SSD can be restore in just 4 minutes!)Edited by _GTech - 3/12/11 at 8:20am